Certain highly fluorinated hydrofluorocarbon refrigerants, 1,1,1,2-tetrafluoroethane (HFC-134a) for example, developed in the mid-1980s and commercialized in the early 1990s to replace ozone depleting chlorofluorocarbon (CFC) refrigerants, are coming under increased regulatory pressure due to their relatively high global warming potential (GWP) and purported impact on global warming. Refrigeration and air conditioning industry solutions include designing essentially leak-free hydrofluorocarbon-based refrigeration systems, as well as possibly transitioning from higher GWP to lower GWP refrigerants, including certain hydrofluorocarbons (e.g., 1,1-difluoroethane (HFC-152a)) and hydrocarbons as well as compounds such as carbon dioxide, ammonia, and dimethyl ether. These new solutions are accompanied by concerns related to leak-free designs, as well as concerns around flammability and toxicity of the lower GWP refrigerants. The industry needs to be able to detect and/or differentiate from background gases, and optionally quantify leaking refrigerants as it transitions to lower GWP refrigerants, preferably, doing so accurately, reproducibly and cost effectively.
For example, where the solution involves carbon dioxide used as a refrigerant, detection, differentiating from background (atmospheric) carbon dioxide concentration (which may vary, e.g., in a sealed space depending on occupant respiration, efficiency of combustion and emission control apparatus, etc.), and quantifying leaking carbon dioxide refrigerant is a difficult problem to solve with current apparatus and methods.
Also, where the solution involves 1,1-difluoroethane (HFC-152a) as the working fluid in a sealed vehicle's air conditioning system, detection, differentiating from background 1,1-difluoroethane concentration (which may be separately present due to usage of HFC-152a as aerosol propellant and polymer foam blowing agent), and quantifying leaking 1,1-difluoroethane refrigerant is a difficult problem to solve with currently available apparatus and methods. Some current detectors are also less sensitive to hydrofluorocarbons and have more difficulty detecting HFC leaks than compounds containing chlorine.
The present invention, the use of the compositions of the present invention, and the method for detecting the compositions of the present invention meet the industry needs.